+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
--- --
--- S Y S T E M . T A S K _ P R I M I T I V E S . O P E R A T I O N S --
--- --
--- B o d y --
--- --
--- $Revision: 1.2.10.1 $
--- --
--- Copyright (C) 1992-2001, Free Software Foundation, Inc. --
--- --
--- GNARL is free software; you can redistribute it and/or modify it under --
--- terms of the GNU General Public License as published by the Free Soft- --
--- ware Foundation; either version 2, or (at your option) any later ver- --
--- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
--- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
--- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
--- for more details. You should have received a copy of the GNU General --
--- Public License distributed with GNARL; see file COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
--- --
--- As a special exception, if other files instantiate generics from this --
--- unit, or you link this unit with other files to produce an executable, --
--- this unit does not by itself cause the resulting executable to be --
--- covered by the GNU General Public License. This exception does not --
--- however invalidate any other reasons why the executable file might be --
--- covered by the GNU Public License. --
--- --
--- GNARL was developed by the GNARL team at Florida State University. --
--- Extensive contributions were provided by Ada Core Technologies Inc. --
--- --
-------------------------------------------------------------------------------
-
--- This is a NT (native) version of this package.
-
--- This package contains all the GNULL primitives that interface directly
--- with the underlying OS.
-
-pragma Polling (Off);
--- Turn off polling, we do not want ATC polling to take place during
--- tasking operations. It causes infinite loops and other problems.
-
-with System.Tasking.Debug;
--- used for Known_Tasks
-
-with Interfaces.C;
--- used for int
--- size_t
-
-with Interfaces.C.Strings;
--- used for Null_Ptr
-
-with System.OS_Interface;
--- used for various type, constant, and operations
-
-with System.Parameters;
--- used for Size_Type
-
-with System.Tasking;
--- used for Ada_Task_Control_Block
--- Task_ID
-
-with System.Soft_Links;
--- used for Defer/Undefer_Abort
--- to initialize TSD for a C thread, in function Self
-
--- Note that we do not use System.Tasking.Initialization directly since
--- this is a higher level package that we shouldn't depend on. For example
--- when using the restricted run time, it is replaced by
--- System.Tasking.Restricted.Initialization
-
-with System.OS_Primitives;
--- used for Delay_Modes
-
-with System.Task_Info;
--- used for Unspecified_Task_Info
-
-with Unchecked_Conversion;
-with Unchecked_Deallocation;
-
-package body System.Task_Primitives.Operations is
-
- use System.Tasking.Debug;
- use System.Tasking;
- use Interfaces.C;
- use Interfaces.C.Strings;
- use System.OS_Interface;
- use System.Parameters;
- use System.OS_Primitives;
-
- pragma Linker_Options ("-Xlinker --stack=0x800000,0x1000");
-
- package SSL renames System.Soft_Links;
-
- ------------------
- -- Local Data --
- ------------------
-
- Environment_Task_ID : Task_ID;
- -- A variable to hold Task_ID for the environment task.
-
- All_Tasks_L : aliased System.Task_Primitives.RTS_Lock;
- -- See comments on locking rules in System.Tasking (spec).
-
- Time_Slice_Val : Integer;
- pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
-
- Dispatching_Policy : Character;
- pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
-
- FIFO_Within_Priorities : constant Boolean := Dispatching_Policy = 'F';
- -- Indicates whether FIFO_Within_Priorities is set.
-
- ---------------------------------
- -- Foreign Threads Detection --
- ---------------------------------
-
- -- The following are used to allow the Self function to
- -- automatically generate ATCB's for C threads that happen to call
- -- Ada procedure, which in turn happen to call the Ada run-time system.
-
- type Fake_ATCB;
- type Fake_ATCB_Ptr is access Fake_ATCB;
- type Fake_ATCB is record
- Stack_Base : Interfaces.C.unsigned := 0;
- -- A value of zero indicates the node is not in use.
- Next : Fake_ATCB_Ptr;
- Real_ATCB : aliased Ada_Task_Control_Block (0);
- end record;
-
- Fake_ATCB_List : Fake_ATCB_Ptr;
- -- A linear linked list.
- -- The list is protected by All_Tasks_L;
- -- Nodes are added to this list from the front.
- -- Once a node is added to this list, it is never removed.
-
- Fake_Task_Elaborated : aliased Boolean := True;
- -- Used to identified fake tasks (i.e., non-Ada Threads).
-
- Next_Fake_ATCB : Fake_ATCB_Ptr;
- -- Used to allocate one Fake_ATCB in advance. See comment in New_Fake_ATCB
-
- ---------------------------------
- -- Support for New_Fake_ATCB --
- ---------------------------------
-
- function New_Fake_ATCB return Task_ID;
- -- Allocate and Initialize a new ATCB. This code can safely be called from
- -- a foreign thread, as it doesn't access implicitly or explicitly
- -- "self" before having initialized the new ATCB.
-
- ------------------------------------
- -- The thread local storage index --
- ------------------------------------
-
- TlsIndex : DWORD;
- pragma Export (Ada, TlsIndex);
- -- To ensure that this variable won't be local to this package, since
- -- in some cases, inlining forces this variable to be global anyway.
-
- ----------------------------------
- -- Utility Conversion Functions --
- ----------------------------------
-
- function To_Task_Id is new Unchecked_Conversion (System.Address, Task_ID);
-
- function To_Address is new Unchecked_Conversion (Task_ID, System.Address);
-
- -------------------
- -- New_Fake_ATCB --
- -------------------
-
- function New_Fake_ATCB return Task_ID is
- Self_ID : Task_ID;
- P, Q : Fake_ATCB_Ptr;
- Succeeded : Boolean;
- Res : BOOL;
-
- begin
- -- This section is ticklish.
- -- We dare not call anything that might require an ATCB, until
- -- we have the new ATCB in place.
-
- Write_Lock (All_Tasks_L'Access);
- Q := null;
- P := Fake_ATCB_List;
-
- while P /= null loop
- if P.Stack_Base = 0 then
- Q := P;
- end if;
-
- P := P.Next;
- end loop;
-
- if Q = null then
-
- -- Create a new ATCB with zero entries.
-
- Self_ID := Next_Fake_ATCB.Real_ATCB'Access;
- Next_Fake_ATCB.Stack_Base := 1;
- Next_Fake_ATCB.Next := Fake_ATCB_List;
- Fake_ATCB_List := Next_Fake_ATCB;
- Next_Fake_ATCB := null;
-
- else
- -- Reuse an existing fake ATCB.
-
- Self_ID := Q.Real_ATCB'Access;
- Q.Stack_Base := 1;
- end if;
-
- -- Record this as the Task_ID for the current thread.
-
- Self_ID.Common.LL.Thread := GetCurrentThread;
-
- Res := TlsSetValue (TlsIndex, To_Address (Self_ID));
- pragma Assert (Res = True);
-
- -- Do the standard initializations
-
- System.Tasking.Initialize_ATCB
- (Self_ID, null, Null_Address, Null_Task, Fake_Task_Elaborated'Access,
- System.Priority'First, Task_Info.Unspecified_Task_Info, 0, Self_ID,
- Succeeded);
- pragma Assert (Succeeded);
-
- -- Finally, it is safe to use an allocator in this thread.
-
- if Next_Fake_ATCB = null then
- Next_Fake_ATCB := new Fake_ATCB;
- end if;
-
- Self_ID.Master_of_Task := 0;
- Self_ID.Master_Within := Self_ID.Master_of_Task + 1;
-
- for L in Self_ID.Entry_Calls'Range loop
- Self_ID.Entry_Calls (L).Self := Self_ID;
- Self_ID.Entry_Calls (L).Level := L;
- end loop;
-
- Self_ID.Common.State := Runnable;
- Self_ID.Awake_Count := 1;
-
- -- Since this is not an ordinary Ada task, we will start out undeferred
-
- Self_ID.Deferral_Level := 0;
-
- System.Soft_Links.Create_TSD (Self_ID.Common.Compiler_Data);
-
- -- ????
- -- The following call is commented out to avoid dependence on
- -- the System.Tasking.Initialization package.
- -- It seems that if we want Ada.Task_Attributes to work correctly
- -- for C threads we will need to raise the visibility of this soft
- -- link to System.Soft_Links.
- -- We are putting that off until this new functionality is otherwise
- -- stable.
- -- System.Tasking.Initialization.Initialize_Attributes_Link.all (T);
-
- -- Must not unlock until Next_ATCB is again allocated.
-
- Unlock (All_Tasks_L'Access);
- return Self_ID;
- end New_Fake_ATCB;
-
- ----------------------------------
- -- Condition Variable Functions --
- ----------------------------------
-
- procedure Initialize_Cond (Cond : access Condition_Variable);
- -- Initialize given condition variable Cond
-
- procedure Finalize_Cond (Cond : access Condition_Variable);
- -- Finalize given condition variable Cond.
-
- procedure Cond_Signal (Cond : access Condition_Variable);
- -- Signal condition variable Cond
-
- procedure Cond_Wait
- (Cond : access Condition_Variable;
- L : access RTS_Lock);
- -- Wait on conditional variable Cond, using lock L
-
- procedure Cond_Timed_Wait
- (Cond : access Condition_Variable;
- L : access RTS_Lock;
- Rel_Time : Duration;
- Timed_Out : out Boolean;
- Status : out Integer);
- -- Do timed wait on condition variable Cond using lock L. The duration
- -- of the timed wait is given by Rel_Time. When the condition is
- -- signalled, Timed_Out shows whether or not a time out occurred.
- -- Status shows whether Cond_Timed_Wait completed successfully.
-
- ---------------------
- -- Initialize_Cond --
- ---------------------
-
- procedure Initialize_Cond (Cond : access Condition_Variable) is
- hEvent : HANDLE;
-
- begin
- hEvent := CreateEvent (null, True, False, Null_Ptr);
- pragma Assert (hEvent /= 0);
- Cond.all := Condition_Variable (hEvent);
- end Initialize_Cond;
-
- -------------------
- -- Finalize_Cond --
- -------------------
-
- -- No such problem here, DosCloseEventSem has been derived.
- -- What does such refer to in above comment???
-
- procedure Finalize_Cond (Cond : access Condition_Variable) is
- Result : BOOL;
-
- begin
- Result := CloseHandle (HANDLE (Cond.all));
- pragma Assert (Result = True);
- end Finalize_Cond;
-
- -----------------
- -- Cond_Signal --
- -----------------
-
- procedure Cond_Signal (Cond : access Condition_Variable) is
- Result : BOOL;
-
- begin
- Result := SetEvent (HANDLE (Cond.all));
- pragma Assert (Result = True);
- end Cond_Signal;
-
- ---------------
- -- Cond_Wait --
- ---------------
-
- -- Pre-assertion: Cond is posted
- -- L is locked.
-
- -- Post-assertion: Cond is posted
- -- L is locked.
-
- procedure Cond_Wait
- (Cond : access Condition_Variable;
- L : access RTS_Lock)
- is
- Result : DWORD;
- Result_Bool : BOOL;
-
- begin
- -- Must reset Cond BEFORE L is unlocked.
-
- Result_Bool := ResetEvent (HANDLE (Cond.all));
- pragma Assert (Result_Bool = True);
- Unlock (L);
-
- -- No problem if we are interrupted here: if the condition is signaled,
- -- WaitForSingleObject will simply not block
-
- Result := WaitForSingleObject (HANDLE (Cond.all), Wait_Infinite);
- pragma Assert (Result = 0);
-
- Write_Lock (L);
- end Cond_Wait;
-
- ---------------------
- -- Cond_Timed_Wait --
- ---------------------
-
- -- Pre-assertion: Cond is posted
- -- L is locked.
-
- -- Post-assertion: Cond is posted
- -- L is locked.
-
- procedure Cond_Timed_Wait
- (Cond : access Condition_Variable;
- L : access RTS_Lock;
- Rel_Time : Duration;
- Timed_Out : out Boolean;
- Status : out Integer)
- is
- Time_Out : DWORD;
- Result : BOOL;
-
- Int_Rel_Time : DWORD;
- Wait_Result : DWORD;
-
- begin
- -- Must reset Cond BEFORE L is unlocked.
-
- Result := ResetEvent (HANDLE (Cond.all));
- pragma Assert (Result = True);
- Unlock (L);
-
- -- No problem if we are interrupted here: if the condition is signaled,
- -- WaitForSingleObject will simply not block
-
- if Rel_Time <= 0.0 then
- Timed_Out := True;
- else
- Int_Rel_Time := DWORD (Rel_Time);
- Time_Out := Int_Rel_Time * 1000 +
- DWORD ((Rel_Time - Duration (Int_Rel_Time)) * 1000.0);
- Wait_Result := WaitForSingleObject (HANDLE (Cond.all), Time_Out);
-
- if Wait_Result = WAIT_TIMEOUT then
- Timed_Out := True;
- Wait_Result := 0;
- else
- Timed_Out := False;
- end if;
- end if;
-
- Write_Lock (L);
-
- -- Ensure post-condition
-
- if Timed_Out then
- Result := SetEvent (HANDLE (Cond.all));
- pragma Assert (Result = True);
- end if;
-
- Status := Integer (Wait_Result);
- end Cond_Timed_Wait;
-
- ------------------
- -- Stack_Guard --
- ------------------
-
- -- The underlying thread system sets a guard page at the
- -- bottom of a thread stack, so nothing is needed.
- -- ??? Check the comment above
-
- procedure Stack_Guard (T : ST.Task_ID; On : Boolean) is
- begin
- null;
- end Stack_Guard;
-
- --------------------
- -- Get_Thread_Id --
- --------------------
-
- function Get_Thread_Id (T : ST.Task_ID) return OSI.Thread_Id is
- begin
- return T.Common.LL.Thread;
- end Get_Thread_Id;
-
- ----------
- -- Self --
- ----------
-
- function Self return Task_ID is
- Self_Id : Task_ID;
-
- begin
- Self_Id := To_Task_Id (TlsGetValue (TlsIndex));
-
- if Self_Id = null then
- return New_Fake_ATCB;
- end if;
-
- return Self_Id;
- end Self;
-
- ---------------------
- -- Initialize_Lock --
- ---------------------
-
- -- Note: mutexes and cond_variables needed per-task basis are
- -- initialized in Initialize_TCB and the Storage_Error is handled.
- -- Other mutexes (such as All_Tasks_Lock, Memory_Lock...) used in
- -- the RTS is initialized before any status change of RTS.
- -- Therefore raising Storage_Error in the following routines
- -- should be able to be handled safely.
-
- procedure Initialize_Lock
- (Prio : System.Any_Priority;
- L : access Lock) is
- begin
- InitializeCriticalSection (L.Mutex'Access);
- L.Owner_Priority := 0;
- L.Priority := Prio;
- end Initialize_Lock;
-
- procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is
- begin
- InitializeCriticalSection (CRITICAL_SECTION (L.all)'Unrestricted_Access);
- end Initialize_Lock;
-
- -------------------
- -- Finalize_Lock --
- -------------------
-
- procedure Finalize_Lock (L : access Lock) is
- begin
- DeleteCriticalSection (L.Mutex'Access);
- end Finalize_Lock;
-
- procedure Finalize_Lock (L : access RTS_Lock) is
- begin
- DeleteCriticalSection (CRITICAL_SECTION (L.all)'Unrestricted_Access);
- end Finalize_Lock;
-
- ----------------
- -- Write_Lock --
- ----------------
-
- procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
- begin
- L.Owner_Priority := Get_Priority (Self);
-
- if L.Priority < L.Owner_Priority then
- Ceiling_Violation := True;
- return;
- end if;
-
- EnterCriticalSection (L.Mutex'Access);
-
- Ceiling_Violation := False;
- end Write_Lock;
-
- procedure Write_Lock (L : access RTS_Lock) is
- begin
- EnterCriticalSection (CRITICAL_SECTION (L.all)'Unrestricted_Access);
- end Write_Lock;
-
- procedure Write_Lock (T : Task_ID) is
- begin
- EnterCriticalSection
- (CRITICAL_SECTION (T.Common.LL.L)'Unrestricted_Access);
- end Write_Lock;
-
- ---------------
- -- Read_Lock --
- ---------------
-
- procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
- begin
- Write_Lock (L, Ceiling_Violation);
- end Read_Lock;
-
- ------------
- -- Unlock --
- ------------
-
- procedure Unlock (L : access Lock) is
- begin
- LeaveCriticalSection (L.Mutex'Access);
- end Unlock;
-
- procedure Unlock (L : access RTS_Lock) is
- begin
- LeaveCriticalSection (CRITICAL_SECTION (L.all)'Unrestricted_Access);
- end Unlock;
-
- procedure Unlock (T : Task_ID) is
- begin
- LeaveCriticalSection
- (CRITICAL_SECTION (T.Common.LL.L)'Unrestricted_Access);
- end Unlock;
-
- -----------
- -- Sleep --
- -----------
-
- procedure Sleep
- (Self_ID : Task_ID;
- Reason : System.Tasking.Task_States) is
- begin
- pragma Assert (Self_ID = Self);
-
- Cond_Wait (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access);
-
- if Self_ID.Deferral_Level = 0
- and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
- then
- Unlock (Self_ID);
- raise Standard'Abort_Signal;
- end if;
- end Sleep;
-
- -----------------
- -- Timed_Sleep --
- -----------------
-
- -- This is for use within the run-time system, so abort is
- -- assumed to be already deferred, and the caller should be
- -- holding its own ATCB lock.
-
- procedure Timed_Sleep
- (Self_ID : Task_ID;
- Time : Duration;
- Mode : ST.Delay_Modes;
- Reason : System.Tasking.Task_States;
- Timedout : out Boolean;
- Yielded : out Boolean)
- is
- Check_Time : constant Duration := Monotonic_Clock;
- Rel_Time : Duration;
- Abs_Time : Duration;
- Result : Integer;
-
- Local_Timedout : Boolean;
-
- begin
- Timedout := True;
- Yielded := False;
-
- if Mode = Relative then
- Rel_Time := Time;
- Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time;
- else
- Rel_Time := Time - Check_Time;
- Abs_Time := Time;
- end if;
-
- if Rel_Time > 0.0 then
- loop
- exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
- or else Self_ID.Pending_Priority_Change;
-
- Cond_Timed_Wait (Self_ID.Common.LL.CV'Access,
- Self_ID.Common.LL.L'Access, Rel_Time, Local_Timedout, Result);
-
- exit when Abs_Time <= Monotonic_Clock;
-
- if not Local_Timedout then
- -- somebody may have called Wakeup for us
- Timedout := False;
- exit;
- end if;
-
- Rel_Time := Abs_Time - Monotonic_Clock;
- end loop;
- end if;
- end Timed_Sleep;
-
- -----------------
- -- Timed_Delay --
- -----------------
-
- procedure Timed_Delay
- (Self_ID : Task_ID;
- Time : Duration;
- Mode : ST.Delay_Modes)
- is
- Check_Time : constant Duration := Monotonic_Clock;
- Rel_Time : Duration;
- Abs_Time : Duration;
- Result : Integer;
- Timedout : Boolean;
-
- begin
- -- Only the little window between deferring abort and
- -- locking Self_ID is the reason we need to
- -- check for pending abort and priority change below! :(
-
- SSL.Abort_Defer.all;
- Write_Lock (Self_ID);
-
- if Mode = Relative then
- Rel_Time := Time;
- Abs_Time := Time + Check_Time;
- else
- Rel_Time := Time - Check_Time;
- Abs_Time := Time;
- end if;
-
- if Rel_Time > 0.0 then
- Self_ID.Common.State := Delay_Sleep;
-
- loop
- if Self_ID.Pending_Priority_Change then
- Self_ID.Pending_Priority_Change := False;
- Self_ID.Common.Base_Priority := Self_ID.New_Base_Priority;
- Set_Priority (Self_ID, Self_ID.Common.Base_Priority);
- end if;
-
- exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
-
- Cond_Timed_Wait (Self_ID.Common.LL.CV'Access,
- Self_ID.Common.LL.L'Access, Rel_Time, Timedout, Result);
-
- exit when Abs_Time <= Monotonic_Clock;
-
- Rel_Time := Abs_Time - Monotonic_Clock;
- end loop;
-
- Self_ID.Common.State := Runnable;
- end if;
-
- Unlock (Self_ID);
- Yield;
- SSL.Abort_Undefer.all;
- end Timed_Delay;
-
- ------------
- -- Wakeup --
- ------------
-
- procedure Wakeup (T : Task_ID; Reason : System.Tasking.Task_States) is
- begin
- Cond_Signal (T.Common.LL.CV'Access);
- end Wakeup;
-
- -----------
- -- Yield --
- -----------
-
- procedure Yield (Do_Yield : Boolean := True) is
- begin
- if Do_Yield then
- Sleep (0);
- end if;
- end Yield;
-
- ------------------
- -- Set_Priority --
- ------------------
-
- type Prio_Array_Type is array (System.Any_Priority) of Integer;
- pragma Atomic_Components (Prio_Array_Type);
-
- Prio_Array : Prio_Array_Type;
- -- Global array containing the id of the currently running task for
- -- each priority.
- --
- -- Note: we assume that we are on a single processor with run-til-blocked
- -- scheduling.
-
- procedure Set_Priority
- (T : Task_ID;
- Prio : System.Any_Priority;
- Loss_Of_Inheritance : Boolean := False)
- is
- Res : BOOL;
- Array_Item : Integer;
-
- begin
- Res := SetThreadPriority
- (T.Common.LL.Thread, Interfaces.C.int (Underlying_Priorities (Prio)));
- pragma Assert (Res = True);
-
- -- ??? Work around a bug in NT 4.0 SP3 scheduler
- -- It looks like when a task with Thread_Priority_Idle (using RT class)
- -- never reaches its time slice (e.g by doing multiple and simple RV,
- -- see CXD8002), the scheduler never gives higher priority task a
- -- chance to run.
- -- Note that this works fine on NT 4.0 SP1
-
- if Time_Slice_Val = 0
- and then Underlying_Priorities (Prio) = Thread_Priority_Idle
- and then Loss_Of_Inheritance
- then
- Sleep (20);
- end if;
-
- if FIFO_Within_Priorities then
-
- -- Annex D requirement [RM D.2.2 par. 9]:
- -- If the task drops its priority due to the loss of inherited
- -- priority, it is added at the head of the ready queue for its
- -- new active priority.
-
- if Loss_Of_Inheritance
- and then Prio < T.Common.Current_Priority
- then
- Array_Item := Prio_Array (T.Common.Base_Priority) + 1;
- Prio_Array (T.Common.Base_Priority) := Array_Item;
-
- loop
- -- Let some processes a chance to arrive
-
- Yield;
-
- -- Then wait for our turn to proceed
-
- exit when Array_Item = Prio_Array (T.Common.Base_Priority)
- or else Prio_Array (T.Common.Base_Priority) = 1;
- end loop;
-
- Prio_Array (T.Common.Base_Priority) :=
- Prio_Array (T.Common.Base_Priority) - 1;
- end if;
- end if;
-
- T.Common.Current_Priority := Prio;
- end Set_Priority;
-
- ------------------
- -- Get_Priority --
- ------------------
-
- function Get_Priority (T : Task_ID) return System.Any_Priority is
- begin
- return T.Common.Current_Priority;
- end Get_Priority;
-
- ----------------
- -- Enter_Task --
- ----------------
-
- -- There were two paths were we needed to call Enter_Task :
- -- 1) from System.Task_Primitives.Operations.Initialize
- -- 2) from System.Tasking.Stages.Task_Wrapper
- --
- -- The thread initialisation has to be done only for the first case.
- --
- -- This is because the GetCurrentThread NT call does not return the
- -- real thread handler but only a "pseudo" one. It is not possible to
- -- release the thread handle and free the system ressources from this
- -- "pseudo" handle. So we really want to keep the real thread handle
- -- set in System.Task_Primitives.Operations.Create_Task during the
- -- thread creation.
-
- procedure Enter_Task (Self_ID : Task_ID) is
- procedure Init_Float;
- pragma Import (C, Init_Float, "__gnat_init_float");
- -- Properly initializes the FPU for x86 systems.
-
- Succeeded : BOOL;
-
- begin
- Succeeded := TlsSetValue (TlsIndex, To_Address (Self_ID));
- pragma Assert (Succeeded = True);
- Init_Float;
-
- Self_ID.Common.LL.Thread_Id := GetCurrentThreadId;
-
- Lock_All_Tasks_List;
-
- for J in Known_Tasks'Range loop
- if Known_Tasks (J) = null then
- Known_Tasks (J) := Self_ID;
- Self_ID.Known_Tasks_Index := J;
- exit;
- end if;
- end loop;
-
- Unlock_All_Tasks_List;
- end Enter_Task;
-
- --------------
- -- New_ATCB --
- --------------
-
- function New_ATCB (Entry_Num : Task_Entry_Index) return Task_ID is
- begin
- return new Ada_Task_Control_Block (Entry_Num);
- end New_ATCB;
-
- ----------------------
- -- Initialize_TCB --
- ----------------------
-
- procedure Initialize_TCB (Self_ID : Task_ID; Succeeded : out Boolean) is
- begin
- Initialize_Cond (Self_ID.Common.LL.CV'Access);
- Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
- Succeeded := True;
- end Initialize_TCB;
-
- -----------------
- -- Create_Task --
- -----------------
-
- procedure Create_Task
- (T : Task_ID;
- Wrapper : System.Address;
- Stack_Size : System.Parameters.Size_Type;
- Priority : System.Any_Priority;
- Succeeded : out Boolean)
- is
- hTask : HANDLE;
- TaskId : aliased DWORD;
-
- -- ??? The fact that we can't use PVOID because the compiler
- -- gives a "PVOID is not visible" error is a GNAT bug.
- -- The strange thing is that the file compiles fine during a regular
- -- build.
-
- pTaskParameter : System.OS_Interface.PVOID;
- dwStackSize : DWORD;
- Result : DWORD;
- Entry_Point : PTHREAD_START_ROUTINE;
-
- function To_PTHREAD_START_ROUTINE is new
- Unchecked_Conversion (System.Address, PTHREAD_START_ROUTINE);
-
- begin
- pTaskParameter := To_Address (T);
-
- if Stack_Size = Unspecified_Size then
- dwStackSize := DWORD (Default_Stack_Size);
-
- elsif Stack_Size < Minimum_Stack_Size then
- dwStackSize := DWORD (Minimum_Stack_Size);
-
- else
- dwStackSize := DWORD (Stack_Size);
- end if;
-
- Entry_Point := To_PTHREAD_START_ROUTINE (Wrapper);
-
- hTask := CreateThread
- (null,
- dwStackSize,
- Entry_Point,
- pTaskParameter,
- DWORD (Create_Suspended),
- TaskId'Unchecked_Access);
-
- -- Step 1: Create the thread in blocked mode
-
- if hTask = 0 then
- raise Storage_Error;
- end if;
-
- -- Step 2: set its TCB
-
- T.Common.LL.Thread := hTask;
-
- -- Step 3: set its priority (child has inherited priority from parent)
-
- Set_Priority (T, Priority);
-
- -- Step 4: Now, start it for good:
-
- Result := ResumeThread (hTask);
- pragma Assert (Result = 1);
-
- Succeeded := Result = 1;
- end Create_Task;
-
- ------------------
- -- Finalize_TCB --
- ------------------
-
- procedure Finalize_TCB (T : Task_ID) is
- Self_ID : Task_ID := T;
- Result : DWORD;
- Succeeded : BOOL;
-
- procedure Free is new
- Unchecked_Deallocation (Ada_Task_Control_Block, Task_ID);
-
- begin
- Finalize_Lock (T.Common.LL.L'Access);
- Finalize_Cond (T.Common.LL.CV'Access);
-
- if T.Known_Tasks_Index /= -1 then
- Known_Tasks (T.Known_Tasks_Index) := null;
- end if;
-
- -- Wait for the thread to terminate then close it. this is needed
- -- to release system ressources.
-
- Result := WaitForSingleObject (T.Common.LL.Thread, Wait_Infinite);
- pragma Assert (Result /= WAIT_FAILED);
- Succeeded := CloseHandle (T.Common.LL.Thread);
- pragma Assert (Succeeded = True);
-
- Free (Self_ID);
- end Finalize_TCB;
-
- ---------------
- -- Exit_Task --
- ---------------
-
- procedure Exit_Task is
- begin
- ExitThread (0);
- end Exit_Task;
-
- ----------------
- -- Abort_Task --
- ----------------
-
- procedure Abort_Task (T : Task_ID) is
- begin
- null;
- end Abort_Task;
-
- ----------------------
- -- Environment_Task --
- ----------------------
-
- function Environment_Task return Task_ID is
- begin
- return Environment_Task_ID;
- end Environment_Task;
-
- -------------------------
- -- Lock_All_Tasks_List --
- -------------------------
-
- procedure Lock_All_Tasks_List is
- begin
- Write_Lock (All_Tasks_L'Access);
- end Lock_All_Tasks_List;
-
- ---------------------------
- -- Unlock_All_Tasks_List --
- ---------------------------
-
- procedure Unlock_All_Tasks_List is
- begin
- Unlock (All_Tasks_L'Access);
- end Unlock_All_Tasks_List;
-
- ----------------
- -- Initialize --
- ----------------
-
- procedure Initialize (Environment_Task : Task_ID) is
- Res : BOOL;
- begin
- Environment_Task_ID := Environment_Task;
-
- if Time_Slice_Val = 0 or else FIFO_Within_Priorities then
- Res := OS_Interface.SetPriorityClass
- (GetCurrentProcess, Realtime_Priority_Class);
- end if;
-
- TlsIndex := TlsAlloc;
-
- -- Initialize the lock used to synchronize chain of all ATCBs.
-
- Initialize_Lock (All_Tasks_L'Access, All_Tasks_Level);
-
- Environment_Task.Common.LL.Thread := GetCurrentThread;
- Enter_Task (Environment_Task);
-
- -- Create a free ATCB for use on the Fake_ATCB_List
-
- Next_Fake_ATCB := new Fake_ATCB;
- end Initialize;
-
- ---------------------
- -- Monotonic_Clock --
- ---------------------
-
- function Monotonic_Clock return Duration
- renames System.OS_Primitives.Monotonic_Clock;
-
- -------------------
- -- RT_Resolution --
- -------------------
-
- function RT_Resolution return Duration is
- begin
- return 0.000_001; -- 1 micro-second
- end RT_Resolution;
-
- ----------------
- -- Check_Exit --
- ----------------
-
- -- Dummy versions. The only currently working versions is for solaris
- -- (native).
-
- function Check_Exit (Self_ID : ST.Task_ID) return Boolean is
- begin
- return True;
- end Check_Exit;
-
- --------------------
- -- Check_No_Locks --
- --------------------
-
- function Check_No_Locks (Self_ID : ST.Task_ID) return Boolean is
- begin
- return True;
- end Check_No_Locks;
-
- ------------------
- -- Suspend_Task --
- ------------------
-
- function Suspend_Task
- (T : ST.Task_ID;
- Thread_Self : Thread_Id) return Boolean is
- begin
- if T.Common.LL.Thread /= Thread_Self then
- return SuspendThread (T.Common.LL.Thread) = NO_ERROR;
- else
- return True;
- end if;
- end Suspend_Task;
-
- -----------------
- -- Resume_Task --
- -----------------
-
- function Resume_Task
- (T : ST.Task_ID;
- Thread_Self : Thread_Id) return Boolean is
- begin
- if T.Common.LL.Thread /= Thread_Self then
- return ResumeThread (T.Common.LL.Thread) = NO_ERROR;
- else
- return True;
- end if;
- end Resume_Task;
-
-end System.Task_Primitives.Operations;
projects / msp430-gcc.git / blobdiff